Approval and Promulgation of Implementation Plans; Utah; 2017 Base Year Inventories for the 2015 8-Hour Ozone National Ambient Air Quality Standard for the Uinta Basin, Northern Wasatch Front and Southern Wasatch Front Nonattainment Areas

The Environmental Protection Agency (EPA) is proposing to approve a state implementation plan (SIP) revision submitted by the State of Utah. The revision fulfills the base year inventory requirement for the 2015 8-hour ozone national ambient air quality standard (NAAQS) for the Uinta Basin, Northern Wasatch Front, and Southern Wasatch Front nonattainment areas. Utah submitted the base year emissions inventories to meet, in part, the nonattainment requirements for Marginal ozone nonattainment areas under the 2015 8- hour ozone NAAQS. EPA is taking this action pursuant to sections 110, 172, and 182 of the Clean Air Act (CAA).